Symmetrical windsurfing board

ABSTRACT

A windsurfing board may include an elongated hull having an upper deck side, a bottom side, a geometrical midpoint on the bottom side, a geometrical axis x extending through the midpoint and along the length of the elongated hull, a geometrical transverse axis y extending through the midpoint and in a direction that is perpendicular to the axis x, and a geometrical vertical axis z extending through the midpoint and in a direction that is perpendicular to both the axis x and the axis y. The hull may include one single hull body. The windsurfing board may also include a universal joint and at least one lateral resistance inducing projection projecting from the bottom. The bottom side of the windsurfing board may be symmetrical around the axis y, so that the parts of the bottom side that are divided by the axis y are mirror images of each other.

TECHNICAL FIELD

The present invention relates to a windsurfing board.

BACKGROUND ART

Windsurfing as a water sport has been around for a long time and the windsurfing boards have evolved intensively during the last decades, from large and heavy platforms requiring large sails to move, to a variety of boards, from large beginner boards to small advanced boards requiring strong wind and speed to even float. Some features of windsurfing boards have however remained constant. The hull of the board has a mast that is fastened on the top deck part of the board a bit to the forward part, one or more fins are placed at the tail underside of the board and on beginner boards, a centerboard is often present fastened on the bottom side of the board. The center board is often short relative the length of the board and centered in the middle to prevent lateral gliding when sailing and to provide a pivot grip point in the water when turning.

When sailing in a direction the windsurfer will stand centered or slightly to the aft side of the board, holding the sail using a boom that is connected to mast and sail. When turning the board the beginners choice is to walk around the mast, which is an act of balance since the mast is positioned in the front of the board and the surfers weight and thereby the center of mass will have to be moved to the front and back again with the danger of getting weight too forward on the board or too much to the sides so that the surfer looses balance and falls in the water. An advanced windsurfer might change side of the sail in front of his body while remaining at the center of the board and by that gain time and avoid the risk of losing balance while moving on the board, instead moving the risk to balancing the sail in the wind when changing side of it.

For beginners the moving maneuver walking around the mast is often the most challenging part of learning how to windsurf. When trying to turn and circle the mast many beginners fall into the water and have to swim or be dragged to shore. To swim with a windsurfing board or drag it behind a boat is a time consuming task which is also very tiresome. The learning process for the beginner is thus slowed down since less time is used to actually learn how to windsurf.

SUMMARY OF THE INVENTION

It is an object of the present invention to improve the current state of the art, to solve the above problems, and to provide an improved windsurfing board that is easy to learn windsurfing with. These and other objects are achieved by a windsurfing board comprising an elongated hull having an upper deck side, a bottom side, a geometrical midpoint on said bottom side, a geometrical axis x through said midpoint extending along the length of said elongated hull, a geometrical transverse axis y through said midpoint that is perpendicular to said axis x, a geometrical vertical axis z through said midpoint perpendicular to both the axis x and the axis y, the hull comprising one single hull body, a mounting position for a universal joint, and at least one lateral resistance inducing projection projecting from said bottom side. The windsurfing board is characterized in that said bottom side of the windsurfing board is symmetrical around said axis y, so that the parts of the bottom side that are divided by the axis y are mirror images of each other. The term lateral resistance inducing projection is means a projection that will create lateral resistance while sailing, i.e. e.g. a keel or a fin. The lateral resistance inducing projection can be shaped as a planar projection or as shape that is elongated along the hull elongation, and has low resistance in the directions of travel of the windsurfing board, but presents a high resistance to the water in the lateral direction of the board, i.e. in the direction of the axis y.

The symmetrical bottom side of the surf board leads to a number of advantages for the windsurfer. Since the windsurfing board will sail equally good in both directions, the windsurfer will not have to turn the board around to change direction. This is especially advantageous for beginners who have problems learning to turn the windsurfing board around. When wanting to sail in the opposite direction, the windsurfer can simply just change side of the sail as he would in a jibe, meaning that he can continue standing at the same side of the sail at a spot very close to the spot where he stood before shifting direction. This will require a minimum of movement and thus a minimum of balance when shifting to the opposite direction.

According to a preferred embodiment of the present invention the said at least one lateral resistance inducing projection projecting from said bottom side is at least one keel member. The keel member will create lateral resistance that will keep the board from sliding sideways, i.e. in the transverse direction to the direction of travel, or at least reduce the lateral movement.

According to a preferred embodiment of the present invention the windsurfing board is further symmetrical around said axis x, so that the parts of the bottom side that are divided by the axis x are mirror images of each other. It is natural that these two sides of the windsurfing boards are symmetrical as well, although it would be possible to have small variations between the two sides that are divided by the axis x.

According to a preferred embodiment of the present invention the structure of said top deck side of the windsurfing board is symmetrical around said axis y, so that the parts of the top deck side that are divided by the axis y are mirror images of each other. It is further preferred that the top deck side of the windsurfing board further is symmetrical around said axis x, so that the parts of the top deck side that are divided by the axis x are mirror images of each other. This is natural since the invention concerns a symmetrical board without a dedicated “stern” or “aft”. It is, however possible to build a functional board according the present invention with slight differences on the upper deck side as long as the bottom side is symmetrical.

According to one specific embodiment of the present invention the at least one keel member of the windsurfing board is elongated and substantially extends from one end of said hull to the other end along or parallel to said axis x. It is further preferred that the at least one keel member of the windsurfing board is elongated having a length from one end to the other end of up to 100% of the length of said elongated hull.

The keel member will create lateral resistance and thus prevent, as all keels on water vessels are meant to, the board from drifting with the wind in the lateral direction of the board along the axis y while sailing according to the principles of sailing. A long keel member that extends along a large part of the hull is advantageous if it is desired that the board should not turn easily, e.g. if a beginner wants to windsurf from the shore, shift direction, and sail back again. The keel member is of course substantially centered around the midpoint of the bottom side of the windsurfing board in the direction of the axis x, to keep the board symmetrical.

Moreover, according to one embodiment the at least one keel member of the windsurfing board is shallow with a height of up to 30 cm. A shallow keel member will make it easy to drag the windsurfing board in the sand of a beach without turning the windsurfing board. It is further also easy to place the board in the sand and stand on it for practicing maneuvers on land.

According to a further preferred embodiment of the present invention the keel member is a lateral resistance inducing projection protruding in the z-x plane or a plane that is parallel to the z-x plane.

The keel member that preferably is shallow for reasons discussed above, can be substantially perpendicular to the bottom side, i.e. parallel to the z-x plane, which is almost a requirement for the functionality if there is only one keel member. When having multiple keel members an even number of these keels could be angled to the z-x plane, pair wise in opposite directions. The reason for that could be to optimize the board for stability on land, for manufacturing reasons or to have some keel members that increase their lateral resistance when the board lean to one side.

According to a still further preferred embodiment of the present invention the keel member has a deeper part in the middle for presenting a pivot point for turning the windsurfing board, and the keel member is protruding in the z-x plane. The deeper middle part of the keel member, usually called a dagger board, will make the board easier to turn around the midpoint. After a beginner has learned how to windsurf back and forth from the shore, it is time to learn how to turn the board in a wanted direction. It is then wanted to add the deeper middle keel member to make the turning operation easier to perform. The dagger board is preferably detachable so that it can be added to the board when it is time for the windsurfer to practice turning. The deeper middle part of the keel member or the dagger board will create more lateral resistance so that the windsurfing board will be able to sail higher to the wind.

According to a still further preferred embodiment of the present invention the windsurfing board has at least two of said keel members. If the beach or shore is hard, it could be hard to push even a single shallow keel member into the sand/ground to avoid pivoting of the board when standing on it for practicing windsurfing on land. Having two or multiple keels the windsurfing board will stand stable on the ground and it is no longer necessary to press the keel member down in the sand/ground.

According to a still further preferred embodiment of the present invention the at least one keel member of the windsurfing board is short in comparison to the elongated hull having a length of up to 40% of the length of said elongated hull. When the surfer has evolved his/her skills and has learned to sail back and forth, and how to turn the board, it might not be wanted to have the long keel member(s) that makes the windsurfing board hard to turn. It will probably by then also not be necessary to practice on land. It is then preferable to have a short and deep keel member, still of course centered around the midpoint for symmetrical reasons. A short keel member makes it easy to turn the board, the board will essential pivot around the keel member.

It is further preferred that the hull of the windsurfing board has a substantially convex bottom side, thus having a rocker at each end presenting a twin tip windsurfing board. The substantially convex shape should be understood as a shape that makes the tips point upwards, as is normal in the nose of a boat or traditional surf board. On surf boards and windsurfing boards the convex nose or tail shape is called a rocker. Since the windsurfing board according to the present invention is intended to sail in both directions, thus not having a dedicated front (nose) and rear (tail) side, both of these ends of the board need to have an angle to the sea to decrease resistance in the water in the two directions the board is intended to travel. The twin tip board that is a result from the two “noses” has some extra advantages, except the normal feature of preventing the front end in the direction of travel from dipping under the water. In an alternative embodiment of the present invention the convex shape is enhanced, i.e. the radius of the curvature is decreased or in other words the windsurfing board ends have more rocker. This is an advantage for the advanced windsurfer, who likes to jump in waves. The natural and pronounced twin tip shape will handle the bigger waves better and also facilitate the landing when jumping, allowing steeper landing angles and allowing the windsurfer to land in either direction.

It is also preferred that the hull of the windsurfing board has at least two fins attached at opposite ends of said elongated hull, symmetrically positioned to each other around said axis y. Fins are normally present on windsurfing boards placed in the aft. On the symmetrical board, fins will have to be placed symmetrical, at least one at each side of the board. It is preferable that the fins are placed far to the ends near the tips of the board, so that they are positioned a bit up on the curvature of the bottom side of the hull. This means that if the windsurfing board lays totally horizontal in the water, the fins will partly be over the water due to the convex shape of the hull. When surfing and standing slightly aft of the mast (in the current travel direction), the fin at the end in the direction of travel, will lift even more from the water and eventually loose grip with the water. For windsurfing purposes it is desired to have fins only at the back side (in the travel direction), why the feature of placing the fins so that they are possible to lift from the water, is essential, especially for windsurfing boards for non-beginner windsurfers.

When having multiple keel members on the bottom side of the windsurfing board, the fins are preferably place in line with keel members. E.g., when having two keel members, preferably four fins are placed, two on each end of the board and two on each keel member. The result will be that the fins will define a rectangle presenting suitable and stable support when placing the windsurfing board on the beach. The fins are in that case preferably ruggedly constructed so that they can stand the load of a person standing on the windsurfing board while it is placed on land. A further advantage of this configuration is that the windsurfing board can be used as a sun bed when the beginner windsurfer wants to take a break and rest before continuing the learning process.

According to a still further preferred embodiment of the present invention at least a part of the at least one keel member is detachable and replaceable using at least one mounting position in the hull. By having detachable parts of the keel member(s) the type of keel used can be changed as the windsurfer evolve from a beginner who only wants to sail back and forth, e.g. having a long keel member, to a more advanced beginner who wants to learn how to turn using the keel member with a deeper part in the middle. The detachable feature makes it possible to change the middle part of the keel member to suit users at different stages in their learning process.

According to a still further preferred embodiment of the present invention the fins are detachable and replaceable from mounting positions in the hull. This feature makes it possible to add and remove fins to and from the windsurfing board according to the windsurfer instructors choice for the beginner. It is also possible to make a windsurfing board that is possible to adjust for both beginners and advanced users. A windsurfing board with one or several very shallow basic keel members can be equipped with only fins to present a windsurfing board for advanced users. The same board can be altered adding a deeper part to the middle of the keel member, presenting a board that is easier to maneuver for a beginner. The fins can be removed for users that are too much beginners to control that the “front” fins are lifted from the water.

According to a still further preferred embodiment of the present invention the windsurfing board further comprises a mast track positioned on said upper deck side over said midpoint along said axis x, wherein the universal joint can be fastened in said mast track at multiple fastening positions. The mast track makes it possible to attach the mast a bit to one side of the board to resemble a traditional windsurfing board that normally have the mast positioned to the front side of the board.

It is further preferred the mounting mechanism for mounting the universal joint to the mast track is a fast coupling, making it possible for a windsurfer to move the universal joint along the mast track during sailing. This is a further feature that can adjust the board along the skill progress of the windsurfer. When controlling the board with the mast positioned at the midpoint of the top deck part, the user can move the mast a bit to the travel direction to increase the driving force of the sail.

According to a further embodiment of the present invention the windsurfing board further comprises a mast track positioned on said upper deck side over said midpoint along said axis y, wherein the universal joint can be fastened in said mast track at multiple fastening positions.

A mast track that is symmetrically placed over the midpoint in the transverse direction to the two travel directions presents additional beneficial features. When placing the universal joint that is holding the sail upwind in the mast track, the board will be able to sail higher to the wind. The forces from the mast downwards on the windsurfing board will also be beneficial to keep the board in an horizontal position. It is preferred that the mast track has a fast coupling for the universal joint of the sail, so that the windsurfer can move the mast along the mast track while sailing.

According to a still further preferred embodiment of the present invention the windsurfing board the upper deck side of the hull is color coded having one color on one side of said axis y and another color on the other side of said axis y. Color coding the deck is a pedagogical feature that can be helpful for the beginner. An instructor can use the colors for explain how the beginner windsurfer should move feet and sail.

It is according to one embodiment also preferred that the top deck part of the hull is color coded with more than two colors. It may for pedagogical reasons be good to have different colors in all four quadrants around the mast. The color coding can also be divided in different ways, e.g. having only two colors that are divided by the axis x instead of the axis y. If having four colors, the four quadrants around the mast could be rotated 45 degrees. The upper deck side of the hull may be color coded having multiple colors placed in a symmetrical structure. The color coding can basically have any symmetrical structure that can be used for pedagogical purposes. Additional to the color coding the deck could also be equipped with markings of what angles to have the sail for sailing in different ways with regard to the direction of the wind (upwind, wind abeam, free wind, run before the wind, etc.).

It is also preferred that the boom used for the sail of the windsurfing board is color coded with the same colors as said top deck part. Also the sail may be color coded with the same colors as said top deck part. Color coding of boom and sail is also intended to be used as pedagogical tools in the learning process of a beginner windsurfer. The color may be matched with the deck colors to help with how to hold the sail and boom in different situations in comparison to where the windsurfers feet are placed.

The deck may also be equipped with foot straps that also may be detachable. An advanced user can then use foot straps which might be good when windsurfing in strong winds, waves and when jumping.

According to a further embodiment the windsurfing board is further equipped with a mast construction bearing a sail and a boom, wherein said mast construction, said sail and said boom all are symmetrically shaped around a vertical axis when having the sail in an upright position. When using a symmetrical sail and boom construction to the symmetrical windsurfing board, the sail only has to be tilted a bit to change the driving force of the board 180 degrees when e.g. sailing with the wind abeam, i.e. with the wind coming in with a 90 degree angle to the axis y of the inventive windsurfing board. The symmetrical sail completes the Symmetrical Soulution of a windsurfing board that is adjustable for different needs and can be used from the complete beginner to advanced wave windsurfers.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects, as well as additional objects, features and advantages of the present invention, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a windsurfing board according to the present invention, having a single keel member and no fins.

FIG. 2 is a perspective view of the windsurfing board shown in FIG. 1 from another angle showing the top deck side, where a moveable universal joint for the sail can be seen in the middle part of a color coded area of the upper deck side.

FIG. 3 a is a perspective view of a windsurfing board according to the present invention, having a single keel member and two fins.

FIG. 3 b is a perspective view of a windsurfing board according to the present invention, having a single keel member, two fins and a centrally placed deeper part of the keel member.

FIG. 3 c is a perspective view of a windsurfing board according to the present invention, having two keel members and four fins.

FIG. 3 d is a perspective view of a windsurfing board according to the present invention having two fins but no keel member.

FIG. 4 is a perspective view of a windsurfing board according to the present invention having two fins and a mast track that is transverse to the travel directions of the board, i.e. it extends along the axis x, symmetrically placed over the midpoint.

FIG. 5 a is a is a perspective view of a windsurfing board according to the present invention, having a single keel member and two fins, with a symmetrical windsurfing sail mounted in the universal joint.

FIG. 5 b is a is a perspective view of a windsurfing board according to the present invention, having a single keel member and two fins, with a conventional windsurfing sail mounted in the universal joint.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

FIG. 1 illustrates a windsurfing board 1 according to the present invention having a symmetrical elongated hull 2, extending with its elongation along a geometrical axis x (x). The bottom side 20 of the hull 2 is symmetrical along its elongation around the geometrical axis y (y), i.e. when travelling in a direction, the front (nose) side in the travelling direction is an identical mirror image of the rear (tail) side. The axis y (y) intersect the axis x (x) at the bottom side geometrical midpoint 3 and is transverse to the axis x (x). A geometrical axis z (z) that is perpendicular to both of the axes x and y is also shown in FIG. 1, illustrating height. The windsurfing board has a symmetrical keel member 4 that protrude in a plane defined by the axis x and the axis z. The keel member 4 is like a long fin extending along substantially all of the hull 2. It should however be noted that the symmetrical keel member 4 also could be short along the axis x in other embodiments.

FIG. 2 shows the same windsurfing board 1 as in FIG. 1, where the top deck side 5 can be seen. In the middle of the top deck side 5, a mast track 6 extending along the axis x is present. The mast track 6 has a universal joint 7 for holding a mast (not shown). The universal joint 7 may be fastened to the mast track using a fast coupling mechanism 8. The universal joint is flexible in a joint as all conventional universal joints for windsurfing boards. On the top deck side 5, two colored areas 9 and 9′ are also shown. The colored areas are positioned around the mast and divided by the axis y. According to other embodiments the color coding can be divided in other ways, according to what the user find helpful and pedagogical in windsurfing training.

FIG. 3 a shows the windsurfing board of FIGS. 1 and 2 with two additional fins 10, 10′. It should be noted that the keel member 4 may be a lot shallower than indicated in FIGS. 3 a and 3 b, depending on how much influence the fins are supposed to have compared to the keel member 4. In FIG. 3 b the windsurfing board of FIG. 3 a is further equipped with a keel member that has a deeper part 11 in the middle for presenting a pivot point for turning the windsurfing board. Also here it should be noted that the windsurfing board may have a much shallower keel member 4 than indicated in the figure to increase the influence of the deeper keel part 11 and the fins 10, 10′. The upper deck side 5 may also be equipped with foot straps 18, of conventional type. The fins are preferably placed in fin boxes (not shown) according to current industry standard to make them easily detachable.

FIG. 3 c shows a windsurfing board 1 having two keel members 40, 40′, each keel member having a pair of fins 10 a-d. The two keel members extend parallel to each other and parallel to the axis x (x). The windsurfing board in FIG. 3 c is symmetrical around both the axis x (x) and the axis y (y). Also here it should be noted that the board may be simplified by removing the fins and the keel members could be shallower than indicated in the figure.

FIG. 3 d shows a windsurfing board 1 according to the present invention having no keel member and two fins 10, 10′. The board has, as can be seen in the figure, a perfectly symmetrical bottom side (20).

FIG. 4 shows a windsurfing board 1 having no keel member and two fins 10, 10′, where only one of the fins 10 can be seen. The windsurfing board has a mast track 26, that is transverse to the direction of travel and placed over the midpoint of the windsurfing board along the axis y (y). The board top deck side is, as can be seen in the figure, still perfectly symmetrical both around the axis x (x) and the axis y (y).

FIG. 5 a shows a windsurfing board according to one embodiment of the present invention having a symmetrical sail 12 attached to the universal joint. The symmetrical sail has a boom 13 and a frame 14 holding the sail. The symmetrical sail 12 is symmetrical along a vertical axis parallel or equal to the axis z (z).

FIG. 5 b shows a windsurfing board according to the present invention having a conventional windsurfing sail 15 with a boom 16. The conventional sail is fastened to a conventional windsurfing mast 17, which is attached to the board in the universal joint 7. The windsurfing boards of FIGS. 4 a and 4 b could of course be any of the boards shown in FIGS. 1-3, having any configuration of keel members, fins and central deeper parts of the keel member as described above.

The booms 13, 16 and sails 12, 15 of FIGS. 4 a and 4 b may also according to the present invention be color coded to match the markings of the upper deck side 5, i.e. the booms may have one color on one side and another on the other side, matching the two colors on the upper deck side.

The windsurfing board 1 according to the present invention making a windsurfing board 1 symmetrical in its propagation through water in combination with a modular construction where fins and keel member parts can be added and removed present a new type of windsurfing board for the complete beginner to advanced windsurfers.

One of the main ideas of the wind surfing board 1 according to the present invention is to provide a windsurfing board that is easy to use for the complete beginner. The symmetrical solution where the windsurfing board has no front and back sides, means that the windsurfer can shift sailing direction without turning the board around, as is necessary with a conventional windsurfing board. The windsurfer can simply change side of the sail 12, 15 and start sailing in the other direction. The solution with a long keel member 4, 40, 40′ along the entire hull 2 leads to a windsurfing board 1 that is harder to change direction with, which for a beginner will present a feeling of a more stable windsurfing board. When having multiple keel elements 40, 40′ the windsurfing board will have more lateral resistance and will thereby become even more stable.

When beginning the windsurfing training, the new windsurfer can, using the inventive windsurfing board 1, start by placing the windsurfing board on the beach and stand on it. The board with two or more keel members is especially advantageous to use for practice on land, since it sits more stable on the ground. The windsurfer instructor can when teaching on land, show the beginner were to stand on the board using the colored deck parts 9, 9′ to illustrate different situations. The colored parts of the boom and sail will also present pedagogical advantages.

When the windsurfer has learned enough of the basics on land, the windsurfing board according to the present invention is moved directly into the water without any need for adding or removing parts of equipment on the windsurfing board. Once in the water, the windsurfer can try the newly learned knowledge on water. Since the board according to the invention is so stable, the difficulty of stability, meaning that the windsurfer has to keep balance on the board, will be substantially reduced compared to conventional beginner windsurfing boards. When sailing the windsurfing board according to the present invention the struggle with conventional boards that the board turns if the sail is kept in the wrong way, will be reduced. The movement will naturally occur also with the inventive windsurfing board, in spite the long keel member(s) 4, 40, 40′, but the turning movement due to the windsurfer holding the sail 12, 15 in the wrong way will be substantially reduced presenting much more time for the beginner to compensate for the mistake and find the correct position of the sail.

The starting direction for the windsurfer is naturally away from the shore, usually a beach. When sailing in that direction it is usually required to change direction 180° after a while to not get too far away from the beach. Since the board has no front and back, the windsurfer may simply change side of the sail to turn 180° and move his/her feet a bit to be correctly positioned to the boom of the sail. In this way the balance act walking around the mast required when turning a conventional windsurfing board is avoided, and the beginner will more likely be able to avoid falling.

When the windsurfer has advanced a bit in the windsurfing training and wants to learn how to turn, the central deeper part 11 according to the present invention is used to present a grip in the water having a pivot point for turning, as shown in FIG. 3 b. The more advanced windsurfer might also want to move the universal joint 7 and thereby the sail using the mast mast track 6 increase performance of the board. When turning the fast coupling mechanism 8 can be used to quickly move the mast to the correct direction. It is also possible to choose to have the universal joint 7 loose on the mast track 6, so that the universal joint 7 can move freely along the mast track 6. Since the force of the sail 12, 15, if handled correctly, is always forward in the wanted travel direction, the universal joint will automatically move to the most forward position of the mast track in the wanted travel direction.

The symmetrical windsurfing board 1 according to the present invention can also be used for advanced windsurfers. The more advanced windsurfer will probably want very shallow keel member(s) with fins, as e.g. the board shown in FIG. 3 c or no keel member at all as shown in FIG. 3 d. Since the symmetrical windsurfing board can be sailed in either direction it is suitable to jump with and make tricks. When e.g. jumping on a wave the board can be landed in either direction presenting new opportunities for the advanced windsurfer. The fins 10, 10′, 10 a-d, which are placed on the upward slope on both ends of the convex bottom side, can be lifted from the water at the front side in the travel direction by using the forces from the sail in the right way and by standing at the right place on the board.

The feature shown in FIG. 4 having a mast track directed in a transverse direction to the directions of travel, or along the axis y (y), presents interesting options for the advanced windsurfer. The advanced user can move the universal joint and thereby the mast up-wind when sailing in upwinds and thereby be able to sail higher against the wind than otherwise. The downward force of the mast will also serve to flatten the board, making it easier for the windsurfer to keep the board flat on the water.

The symmetrical sail shown in FIG. 5 a, will make it even easier for the beginner to learn how to windsurf. The windsurfer will not have to change side of the sail as is necessary using a traditional asymmetrical windsurfing sail. This will make it even easier to keep the balance on the windsurfing board. For the more advanced windsurfers, the symmetrical sail will present options to maneuver faster and to invent new tricks not possible using a asymmetrical sail.

It is understood that other variations in the present invention are contemplated and in some instances, some features of the invention can be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly in a manner consistent with the scope of the invention. 

1. A windsurfing board comprising: an elongated hull having an upper deck side, a bottom side, a geometrical midpoint, on the bottom side, a geometrical axis x extending through the midpoint and along the length of the elongated hull, a geometrical transverse axis y extending through the midpoint and in a direction that is perpendicular to the axis x, a geometrical vertical axis z extending through the midpoint and in a direction that is perpendicular to both the axis x and the axis y, the elongated hull including one single hull body; a mounting position for a universal joint; and at least one lateral resistance inducing projection projecting from the bottom side; wherein the bottom side of the windsurfing board is symmetrical around the axis y, so that parts of the bottom side that are divided by the axis y are mirror images of each other.
 2. The windsurfing board according to claim 1, wherein the at least one lateral resistance inducing projection is at least one keel member.
 3. The windsurfing board according to claim 1, wherein the bottom side of the windsurfing board is symmetrical around the axis x so that parts of the bottom side that are divided by the axis x are mirror images of each other.
 4. The windsurfing board according to claim 2, wherein the at least one keel member is elongated and substantially extends from one end of the elongated hull to the other end along or parallel the axis x.
 5. The windsurfing board according to claim 2, wherein the at least one keel member is elongated having a length from one end to the other end of up to 100% of the length of the elongated hull.
 6. The windsurfing board according to claim 4, wherein the at least one keel member is shallow with a height of up to 30 cm.
 7. The windsurfing board according to claim 2, wherein the keel member is a lateral resistance inducing projection protruding in the z-x plane or a plane that is parallel to the z-x plane.
 8. The windsurfing board according to claim 2, wherein the keel member has a deeper part in the middle for presenting a pivot point for turning the windsurfing board; and wherein the keel member is protruding in the z-x plane.
 9. The windsurfing board according to claim 2, wherein at least two of the keel members are provided.
 10. The windsurfing board according to claim 2, wherein the at least one keel member is short in comparison to the elongated hull having a length of up to 40% of the length of the elongated hull.
 11. The windsurfing board according to claim 1, wherein the elongated hull has a convex bottom side, thus having a rocker at each end presenting a twin tip windsurfing board.
 12. The windsurfing board according to claim 1, wherein at least two of the lateral resistance inducing projections are fins attached at opposite ends of the elongated hull, symmetrically positioned with respect to each other around the axis y.
 13. The windsurfing board according to claim 2, wherein at least a part of the at least one keel member is detachable and replaceable using at least one mounting position in the elongated hull.
 14. The windsurfing board according to claim 12, wherein the fins are detachable and replaceable from mounting positions in the elongated hull.
 15. The windsurfing board according to claim 1, wherein the structure of the upper deck side of the windsurfing board is symmetrical around the axis y, so that parts of the upper deck side that are divided by the axis y are mirror images of each other.
 16. The windsurfing board according to claim 1, wherein the structure of the upper deck side of the windsurfing board is symmetrical around the axis x, so that parts of the upper deck side that are divided by the axis x are mirror images of each other.
 17. The windsurfing board according to claim 1, further comprising a mast track positioned on the upper deck side over the midpoint along the axis y, wherein the universal joint is fastenable in the mast track at multiple fastening positions.
 18. The windsurfing board according to claim 1, wherein the upper deck side of the elongated hull is color coded having one color on one side of the axis y and another color on the other side of the axis y.
 19. The windsurfing board according to claim 1, wherein the upper deck side of the elongated hull is color coded having multiple colors placed in a symmetrical structure.
 20. The windsurfing board according to claim 1, further comprising: a mast construction bearing a sail and a boom; wherein the mast construction, the sail and the boom are symmetrically shaped around a vertical axis parallel or equal to the axis z, when having the sail in an upright position. 